The dental and orthodontic industry has long recognized the need for a careful selection of materials for the construction of crowns, bridges and the like. The dental prostheses must satisfy a number of mechanical requirements such as being able to withstand the stress induced by mastication, hardness, and the like. In addition, the prostheses must possess the necessary biocompatibility characteristics.
For reasons such as those described above, gold and gold alloys such as gold-platinum have been frequently selected for use in the construction of crowns and bridges. However, numerous disadvantages have been occasioned by the use of gold in this manner.
In this connection, the relatively high cost of gold is a significant limiting factor in the utilization of this material in dentistry. Moreover, gold crowns and bridges must be relatively thick to provide necessary strength characteristics, and the often considerable size of such structures limits the thickness of the procelain or plastic aesthetic part of the replacement element (the so-called white surface). Still further, because gold or gold alloys cannot be suitably welded in the mouth, the use of gold in dentistry in the heretofore known prior art is not as flexible in repair and modification as could be obtained using a weldable material wherein individual connections can be broken and reformed.
The problems suggested in the preceding are not intended to be exhaustive, but rather are among many which may tend to reduce the efficiency of prior art dental crowns and bridges. Other problems may also exist; however, those presented above should be sufficient to demonstrate that dental crowns and bridges appearing in the prior art have not been altogether satisfactory.